db.h revision 189827
1/*-
2 * Copyright (c) 1990, 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by the University of
16 *	California, Berkeley and its contributors.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 *	@(#)db.h	8.7 (Berkeley) 6/16/94
34 * $FreeBSD: head/include/db.h 189827 2009-03-14 20:05:27Z das $
35 */
36
37#ifndef _DB_H_
38#define	_DB_H_
39
40#include <sys/types.h>
41#include <sys/cdefs.h>
42
43#include <limits.h>
44
45#define	RET_ERROR	-1		/* Return values. */
46#define	RET_SUCCESS	 0
47#define	RET_SPECIAL	 1
48
49#define	MAX_PAGE_NUMBER	0xffffffff	/* >= # of pages in a file */
50typedef uint32_t	pgno_t;
51#define	MAX_PAGE_OFFSET	65535		/* >= # of bytes in a page */
52typedef uint16_t	indx_t;
53#define	MAX_REC_NUMBER	0xffffffff	/* >= # of records in a tree */
54typedef uint32_t	recno_t;
55
56/* Key/data structure -- a Data-Base Thang. */
57typedef struct {
58	void	*data;			/* data */
59	size_t	 size;			/* data length */
60} DBT;
61
62/* Routine flags. */
63#define	R_CURSOR	1		/* del, put, seq */
64#define	__R_UNUSED	2		/* UNUSED */
65#define	R_FIRST		3		/* seq */
66#define	R_IAFTER	4		/* put (RECNO) */
67#define	R_IBEFORE	5		/* put (RECNO) */
68#define	R_LAST		6		/* seq (BTREE, RECNO) */
69#define	R_NEXT		7		/* seq */
70#define	R_NOOVERWRITE	8		/* put */
71#define	R_PREV		9		/* seq (BTREE, RECNO) */
72#define	R_SETCURSOR	10		/* put (RECNO) */
73#define	R_RECNOSYNC	11		/* sync (RECNO) */
74
75typedef enum { DB_BTREE, DB_HASH, DB_RECNO } DBTYPE;
76
77/*
78 * !!!
79 * The following flags are included in the dbopen(3) call as part of the
80 * open(2) flags.  In order to avoid conflicts with the open flags, start
81 * at the top of the 16 or 32-bit number space and work our way down.  If
82 * the open flags were significantly expanded in the future, it could be
83 * a problem.  Wish I'd left another flags word in the dbopen call.
84 *
85 * !!!
86 * None of this stuff is implemented yet.  The only reason that it's here
87 * is so that the access methods can skip copying the key/data pair when
88 * the DB_LOCK flag isn't set.
89 */
90#if UINT_MAX > 65535
91#define	DB_LOCK		0x20000000	/* Do locking. */
92#define	DB_SHMEM	0x40000000	/* Use shared memory. */
93#define	DB_TXN		0x80000000	/* Do transactions. */
94#else
95#define	DB_LOCK		    0x2000	/* Do locking. */
96#define	DB_SHMEM	    0x4000	/* Use shared memory. */
97#define	DB_TXN		    0x8000	/* Do transactions. */
98#endif
99
100/* Access method description structure. */
101typedef struct __db {
102	DBTYPE type;			/* Underlying db type. */
103	int (*close)(struct __db *);
104	int (*del)(const struct __db *, const DBT *, unsigned int);
105	int (*get)(const struct __db *, const DBT *, DBT *, unsigned int);
106	int (*put)(const struct __db *, DBT *, const DBT *, unsigned int);
107	int (*seq)(const struct __db *, DBT *, DBT *, unsigned int);
108	int (*sync)(const struct __db *, unsigned int);
109	void *internal;			/* Access method private. */
110	int (*fd)(const struct __db *);
111} DB;
112
113#define	BTREEMAGIC	0x053162
114#define	BTREEVERSION	3
115
116/* Structure used to pass parameters to the btree routines. */
117typedef struct {
118#define	R_DUP		0x01	/* duplicate keys */
119	unsigned long	flags;
120	unsigned int	cachesize;	/* bytes to cache */
121	int		maxkeypage;	/* maximum keys per page */
122	int		minkeypage;	/* minimum keys per page */
123	unsigned int	psize;		/* page size */
124	int		(*compare)	/* comparison function */
125			    (const DBT *, const DBT *);
126	size_t		(*prefix)	/* prefix function */
127			    (const DBT *, const DBT *);
128	int		lorder;		/* byte order */
129} BTREEINFO;
130
131#define	HASHMAGIC	0x061561
132#define	HASHVERSION	2
133
134/* Structure used to pass parameters to the hashing routines. */
135typedef struct {
136	unsigned int	bsize;		/* bucket size */
137	unsigned int	ffactor;	/* fill factor */
138	unsigned int	nelem;		/* number of elements */
139	unsigned int	cachesize;	/* bytes to cache */
140	uint32_t			/* hash function */
141		(*hash)(const void *, size_t);
142	int	lorder;		/* byte order */
143} HASHINFO;
144
145/* Structure used to pass parameters to the record routines. */
146typedef struct {
147#define	R_FIXEDLEN	0x01	/* fixed-length records */
148#define	R_NOKEY		0x02	/* key not required */
149#define	R_SNAPSHOT	0x04	/* snapshot the input */
150	unsigned long	flags;
151	unsigned int	cachesize; /* bytes to cache */
152	unsigned int	psize;	/* page size */
153	int		lorder;	/* byte order */
154	size_t		reclen;	/* record length (fixed-length records) */
155	unsigned char	bval;	/* delimiting byte (variable-length records */
156	char	*bfname;	/* btree file name */
157} RECNOINFO;
158
159#ifdef __DBINTERFACE_PRIVATE
160/*
161 * Little endian <==> big endian 32-bit swap macros.
162 *	M_32_SWAP	swap a memory location
163 *	P_32_SWAP	swap a referenced memory location
164 *	P_32_COPY	swap from one location to another
165 */
166#define	M_32_SWAP(a) {							\
167	uint32_t _tmp = a;						\
168	((char *)&a)[0] = ((char *)&_tmp)[3];				\
169	((char *)&a)[1] = ((char *)&_tmp)[2];				\
170	((char *)&a)[2] = ((char *)&_tmp)[1];				\
171	((char *)&a)[3] = ((char *)&_tmp)[0];				\
172}
173#define	P_32_SWAP(a) {							\
174	uint32_t _tmp = *(uint32_t *)a;					\
175	((char *)a)[0] = ((char *)&_tmp)[3];				\
176	((char *)a)[1] = ((char *)&_tmp)[2];				\
177	((char *)a)[2] = ((char *)&_tmp)[1];				\
178	((char *)a)[3] = ((char *)&_tmp)[0];				\
179}
180#define	P_32_COPY(a, b) {						\
181	((char *)&(b))[0] = ((char *)&(a))[3];				\
182	((char *)&(b))[1] = ((char *)&(a))[2];				\
183	((char *)&(b))[2] = ((char *)&(a))[1];				\
184	((char *)&(b))[3] = ((char *)&(a))[0];				\
185}
186
187/*
188 * Little endian <==> big endian 16-bit swap macros.
189 *	M_16_SWAP	swap a memory location
190 *	P_16_SWAP	swap a referenced memory location
191 *	P_16_COPY	swap from one location to another
192 */
193#define	M_16_SWAP(a) {							\
194	uint16_t _tmp = a;						\
195	((char *)&a)[0] = ((char *)&_tmp)[1];				\
196	((char *)&a)[1] = ((char *)&_tmp)[0];				\
197}
198#define	P_16_SWAP(a) {							\
199	uint16_t _tmp = *(uint16_t *)a;					\
200	((char *)a)[0] = ((char *)&_tmp)[1];				\
201	((char *)a)[1] = ((char *)&_tmp)[0];				\
202}
203#define	P_16_COPY(a, b) {						\
204	((char *)&(b))[0] = ((char *)&(a))[1];				\
205	((char *)&(b))[1] = ((char *)&(a))[0];				\
206}
207#endif
208
209__BEGIN_DECLS
210#if __BSD_VISIBLE
211DB *dbopen(const char *, int, int, DBTYPE, const void *);
212#endif
213
214#ifdef __DBINTERFACE_PRIVATE
215DB	*__bt_open(const char *, int, int, const BTREEINFO *, int);
216DB	*__hash_open(const char *, int, int, const HASHINFO *, int);
217DB	*__rec_open(const char *, int, int, const RECNOINFO *, int);
218void	 __dbpanic(DB *dbp);
219#endif
220__END_DECLS
221#endif /* !_DB_H_ */
222